Known image forming apparatuses form an image on a recording medium, such as a sheet, by forming an electrostatic latent image on an image carrying member and developing the electrostatic latent image with a developing agent. In such an image forming apparatus, a cartridge including the image carrying member and a developing device, or a belt unit for conveying a sheet are removably set in a main housing of the image forming apparatus, to enable the maintenance of the image forming apparatuses or a sheet jam clearing operation to be performed.
To remove the cartridge or the belt unit from the main housing, the cartridge or the belt unit is vertically pulled. For example, Japanese Laid-Open Patent Publication No. 2004-206071 discloses a method to remove the belt unit from an upper potion of the image forming apparatus and the cartridge from a front face of the image forming apparatus.
In some image forming apparatuses, the cartridge or the belt unit is horizontally disposed and is pulled horizontally from the main housing. Japanese Laid-Open Patent Publication No. 2003-015378 discloses an image forming apparatus in which the cartridge is horizontally movable.
In the image forming apparatus disclosed in Japanese Laid-Open Patent Publication No. 2004-206071, the belt unit and the cartridge are separately removable from and installable in the image forming apparatus resulting in good maintainability. However, when the belt unit is pulled out from the upper portion of the image forming apparatus, a relatively strong force is required to remove the belt unit from the image forming apparatus.
In the image forming apparatus disclosed in Japanese Laid-Open Patent Publication No. 2003-015378, the cartridge is horizontally moved to remove it from the main housing of the image forming apparatus. Thus, the cartridge can be removed from the image forming apparatus with a lighter force. However, in this image forming apparatus, the cartridge and the belt unit are not individually accessible. Therefore, the cartridge has to be drawn out from the main housing first, for example, before the belt can be replaced, which leads to a complicated replacement operation and results in poor maintainability.